JP2843764B2 - Heating furnace extraction time determination method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for determining a heating furnace extraction time, and more particularly to a method for determining a heating furnace extraction time for determining the extraction time of a material to be extracted from a furnace into a rolling line in a heating furnace material. Things.

[0002]

2. Description of the Related Art Generally, in a continuous hot rolling step, as shown in FIG. 2, one or a plurality of heating furnaces 1 are provided on a roller table called a rolling line. This heating furnace 1
A steel material called a slab is extracted from the slab and rough-rolled by a plurality of rough rolling mills 2 to form a rectangular thick steel plate called a rough bar. This rough bar is further divided into a plurality of finishing mills 3
And finish rolling to the required thickness continuously. The steel plate after finish rolling is wound by the coiler 4 to produce a hot-rolled wide band steel. Conventionally, an operator determines an appropriate extraction pitch while monitoring the position of the steel material on the rolling line and manually extracts the pitch, or automatically extracts the pitch by the following method. FIG. 4 shows an example of such a conventional automatic extraction method introduced in Japanese Patent Application Laid-Open No. Sho 62-30812. That is, in FIG. 4, the rolling schedule calculation of the next extracted material is first performed, and the transfer of the steel material such as the time from the start of the extraction to the arrival at each equipment, the time of the rolling start and the end of the rolling in the rough rolling mill 2 or the finishing rolling mill 3, and the like. Forecasting the schedule and extracting the next extraction material so that the required interval time of the equipment that will be the bottleneck of the next extraction material can be obtained based on the predicted transport schedule of the material extracted immediately before and the actual extraction time of that material. Was decided. At this time, if the material transfer schedule fluctuates due to a sudden failure of the equipment or manual intervention of an operator, problems such as collision of the material, loss of rolling opportunity, and drop in the temperature of the rough bar may occur. In this regard, the extraction time is corrected using the time difference (delay) between the prediction and the actual result of the elapsed time from the extraction of the arrival of each of a plurality of materials and the start and end of the rolling of the plurality of materials. That is, according to the conventional method, it is assumed that there are N places where interference occurs on the rolling line (hereinafter referred to as interference points), and the L-th interference of the material predicted when the k-th preceding material is extracted on time point, oFF time _{respectively,} T ^P onLk, and _T ^P offLk. On the other hand, to turn on the L-th interference point from next extraction material is extracted, the time until the off-t ^P _ONL, a t ^P _OFFL. Time t ^P _onL , t
^{_P offL} is by pre-calculating the schedule of the material, it is predicted calculated from the specifications of the material and equipment. On the other hand, the actual values T ^A _onLk and T ^A _offLk at the time when the k-th preceding material turned off or on the L-th interference point were measured (S
1 '), which is used to correct as follows. That is, all L-th interference points L, k on the rolling line
Among some of the actual value in the preceding material k of the front, ΔT = T ^A -T ^P (also a negative value) is to select the time difference [Delta] T which maximizes (S2 '), the following extraction time T _ext, T _ext = T ⁰ _ext + ΔT is corrected (S3 ′), and the material is extracted at that time.

[0003]

A heating furnace as described above
In the extraction time determination method, on the rolling line,
Point that compares predicted time and actual time as a negotiation point
There is only one steel material near or upstream of the
By removing the fluctuations in the schedule of steel products,
If the schedule of the next extraction material normalizes immediately,
It is thought that it is effective for minutes. However, usually continuous hot pressure
In the rolling process, multiple steel materials are constantly rolled on the rolling line.
ing. Under such conditions, adjust the extraction time of the next extraction material.
Then, the error of prediction / actual at each interference point input one after another
Therefore, the productivity may be greatly deteriorated.
Here, for convenience, steel materials around the heating furnace 1 and the roughing mill 2 are used.
The interference point, especially when the rough rolling mill 2 is on.
The description is limited to the time. As shown in FIG.
Rolled steel material 5a, 5b extracted from several heating furnaces 1
Are rolled by the rough rolling mills 2b and 2c, respectively.
It is assumed that it has been transported. Here, the temperature adjustment of steel
For any reason, the steel material 5a is reentrant in the rough rolling mill 2c.
It is assumed that the conveyance is stopped before and the apparatus enters a waiting state. Then later
The steel material 5b that has been rolled on the side also prevents collision with the steel material 5a.
For this reason, the rough rolling mill 2b is in a waiting state immediately before the biting.
And ΔT₁Seconds later, the steel 5a is released from the waiting state and
Rolled by the rolling mill 2c and the space between the rough rolling mills 2b-2c
When the steel is born, the transfer of the steel 5b is started and the rolling is started.
Begun. Here, when the rough rolling mill 2c is turned on, the predicted value T
₁ ^P _Four, Actual value T₁ ^A _FourTo extract the next extraction material 5c
ΔT₁’= T₁ ^A _Four-T₁ ^P _Four Time difference ΔT₁’(≒ ΔT₁) Will be extracted first and next
Time T⁰ _extModify in addition to. T_{1 ext}= T₁ ⁰ _ext+ ΔT₁’

FIG. 3B shows a state in which the steel material 5c is extracted at the time T _{1 ext} in which it is reflected. Steel 5
“b” indicates a state immediately after the rolling in the rough rolling mill 2b and the rolling in the rough rolling mill 2c. Thereafter, the rough rolling mill 2c is turned on for the steel material 5b, but again, in order to reflect the difference between the initial planned on-time and the actual on-time on the next extracted material, ΔT ₂ ′ = T ₂ ^A ₄ −T ₂ ^P ₄ becomes the time difference ΔT ₂ 'seconds to fix in addition to the next extraction scheduled time ^{_{T 2 0 ext, T 2 ext}} = T 2 0 ext + ΔT 2' have made time and new extraction scheduled time of the next extraction material 5d. However, the time difference ΔT ₂ ′ includes a delay time corresponding to the time difference ΔT ₁ ′ already reflected on the extraction material 5 c, and the steel material 5 a is delayed by the time difference ΔT ₁ ′ second, so that the steel material 5
Although the extraction of c is delayed, the steel material 5d is also delayed. The present invention has improved the method of determining the heating furnace extraction time in order to solve such problems in the prior art, and when a plurality of steel materials extracted at a predetermined extraction pitch are present on a rolling line, and the equipment suddenly It is an object of the present invention to provide a heating furnace extraction time determining method capable of avoiding a loss of rolling opportunity and realizing a smooth operation even if a material conveyance schedule fluctuates due to a failure or manual intervention of an operator.

[0005]

In order to achieve the above object, the present invention relates to a method for extracting a material extracted from a heating furnace to a rolling line.
Reaches one or more detection positions provided on the rolling line.
Predicts the time of arrival and measures the actual time.
Newly extracted based on the delay time relative to the predicted value
In the heating furnace extraction time determining method for correcting the material extraction scheduled time, for each material arriving at each of the above detection positions,
The extraction of each subsequent material already extracted from the delay time
Subtracting the correction time used to correct the scheduled departure time
Determine the delay time, and for each material that arrived at each of the above detection positions,
The maximum value of the actual delay time obtained as described above is added to the scheduled extraction time of the newly extracted material. Furthermore, there is provided a heating furnace extraction time determination method in which the above-mentioned correction time is a time obtained by accumulating past correction times.

[0006]

According to the present invention, when determining the extraction time of the material to be extracted from the furnace to the rolling line in the heating furnace,
First, the time at which the extracted material arrives at one or more detection positions for detecting the material transport time on the rolling line is predicted and measured, and the obtained measured value is predicted.
The delay time for the value is determined. And each of the above detections
For each material that arrives at the location,
Used to correct the above extraction scheduled time for each subsequent extracted material
The actual delay time is calculated by subtracting the correction time.
The values obtained for each material arriving at each of the above detection positions
The maximum value of the actual delay time is added to the scheduled extraction time of the material to be extracted next. As a result, even if the steel material extracted at the specified extraction pitch is on multiple rolling lines and the material transfer schedule fluctuates due to sudden equipment failure or manual intervention by the operator, the next extracted material is By correcting the maximum value of the time difference between the predicted value and the actual value that was found in the above, the material in the furnace after the next extracted material is already reflected in the time difference between the predicted value and the actual value due to the same cause. during the time (real delay that except for the time
By correcting the scheduled extraction time only during the period , loss of the rolling opportunity can be avoided and smooth operation can be realized.
Further, with this, the fuel consumption rate of the heating furnace can be reduced by the amount corresponding to the shortening time of the material time.

[0007]

Embodiments of the present invention will be described below with reference to the accompanying drawings to provide an understanding of the present invention. The following embodiment is an example embodying the present invention and is not intended to limit the technical scope of the present invention. Here, FIG. 1 is an explanatory diagram showing a schematic flow of a heating furnace extraction time method according to one embodiment of the present invention, FIG. 2 is a schematic diagram showing a schematic configuration of a hot rolling line (shared with a conventional example), FIG. FIG. 4 is an explanatory view showing a threading state of a hot rolling line (shared with a conventional example). As shown in FIG. 1, the method for determining the extraction time of the heating furnace according to the present embodiment, when determining the extraction time of the material to be extracted from the furnace to the rolling line in the furnace with the heating furnace, is to convey the material on the rolling line. Predicting and actually measuring the time at which the extracted material arrives at one or more detection positions for detecting the time (S1), and predicting the actual value of the material arriving at each of the detection positions at each of the detection positions. The maximum value of the time obtained by subtracting the correction time based on the delay time for the predicted value of the actual measurement value at each detection position of the material that has arrived at each of the above detection positions before that from the delay time for It is configured to add to the scheduled time (S2, S3). The correction time may be a time obtained by accumulating past correction times. Hereinafter, this method will be described in detail with reference to FIGS. In a continuous hot rolling line as shown in FIG. 2, a slab (corresponding to a material) extracted from a heating furnace 1 is roughly rolled by a rough rolling mill 2 to become a rough bar, and further subjected to finish rolling by a finishing rolling mill 3. After becoming a product, it is wound up by the coiler 4. Here, the detection position is set at the center of each of the rough rolling mills 2, and as a control event, the start of biting of the rough bar into the rough rolling mill, that is, the mill-on, is determined. The case where the rough bars that can be corrected are all the rough bars that reach the above detection position, and a slab is extracted from the furnace without any rough bar on the rolling line will be described.

First, as shown in FIG. 3A, a steel material 5a, which is a slab extracted first, is rolled to form a rough rolling mill 2.
Suppose that the steel material 5a is stopped at the stage where the steel material 5a is reached at the stage upstream of the position c due to the temperature adjustment of the steel material, and is in a waiting state. Then, the steel material 5b that has been rolled rearward also enters a waiting state on the upstream side of the rough rolling mill 2b in order to prevent collision with the steel material 5a. Then, after waiting time ΔT ₁ second, steel 5a
Is released from the waiting state, and when rolling is started by the rough rolling mill 2c, a space is created between the rough rolling mills 2b and 2c, so that the transfer of the steel material 5b is resumed and rolling is started. Here, the predicted value of the on-time of the rough rolling mill 2c from the start of the extraction of the steel material 5a is T ₁ ^A ₄ , and the actual value is T ₁ ^P ₄
Then, the difference is obtained by the extraction pitch control computer 6, and the difference is reflected in the scheduled extraction time of the next extraction material 5c. That is corrected in addition to [Delta] T ₁ beginning of the next extracted scheduled time T ₁ ⁰ _ext of ^{_{'= T 1 A 4 -T 1}} P 4 becomes modification time [Delta] T _1' s steel plates 5c. Here, the reason why the correction time is ΔT ₁ 'second is that there is a slight deviation from the waiting time ΔT ₁ second due to a delay or slippage. T and ^{_{1 ext = T 1 0 ext +}} ΔT 1 ' extraction estimated time of the above T _{1 ext} become time. On the other hand, T
_{When the} steel 5b is also turned on by the rough rolling mill 2b by the time of _{1 ext,} the predicted value of the on-time of the rough rolling mill 2b from the extraction time of the steel 5b is T ₂ ^P ₃ , and the measured value is T 2.
When ₂ ^A _3, the difference calculated, correcting the extracted scheduled time again following extraction member 5c. However, in the second and subsequent corrections to the next extracted material, correction is performed only when the correction value is longer than the correction value determined before that. That is, the steel material 5b
Cases, extraction of the latest represented by the difference between [Delta] T ₁ after modification ^{_{"= T 2 A 3 -T 2}} P 3 becomes modified time [Delta] T _1" is determined at the time the extraction time and extraction scheduled time originally planned correction amount of time when ^{_{(T 1 ext -T 1 0 ext}} ) greater than, and extracted time correction amount [Delta] T ₁ "newly generated instead of this, carrying out the modification of the extraction time. T _{1 ext} = T ₁ ⁰ _ext + ΔT ₁ ”

In this way, it is assumed that the correction occurs every time the steel material reaches the detection position before the next extraction material is started to be extracted, and the estimated time from the extraction of the steel material to the position, the actual time, and the like. If the difference is smaller than the extraction time correction amount before the occurrence of the event, the scheduled extraction time is corrected each time. Next, FIG. 3B shows a state immediately after the steel material 5c is extracted from the heating furnace 1 at the time T _{1 ext} in which these are reflected. The steel material 5a has already been transported from the rough rolling zone to the finish rolling zone.
Has finished rolling in the rough rolling mill 2b, and
Is about to be rolled. Here, the final correction amount (T _{1 ext} −) when the steel material 5c is extracted.
T ₁ ⁰ _ext) all Rafuba that are upstream from the detection position (where at this time is assumed to be recorded for steel 5b). Then, after a while, the rough rolling mill 2c is turned on for the steel material 5b. Here, the extraction pitch control computer 6 also calculates the time difference between the on-time from the initially scheduled extraction start and the actual on-time. The time difference ΔT ₂ ′, which is ΔT ₂ ′ = T ₂ ^A ₄ −T ₂ ^P ₄ , is the difference between the planned and actual results. However, the delay of the steel 5b is caused by the delay of the steel 5a, and the delay is other than that. As long as the steel material 5b is not delayed due to the above factors, there is no great difference even if there is a certain deviation from the delay time of the steel material 5a. Therefore, since the time difference ΔT ₂ ′ includes the delay time corresponding to ΔT ₁ ′ already reflected on the extraction material 5c, the time already reflected on the extraction material 5c is subtracted therefrom and the remainder (corresponding to the actual delay time) ) and it is necessary to correct for the next extraction scheduled time ΔT ₂ ⁰ _ext.
In other ^{_{words, ΔT 2 ext = ΔT 2 0}} ext + ΔT 2 '- have a _(T 1ext -T ₁ ⁰ _ex) becomes time T _{2 ext} to the new extraction scheduled time of the next extraction material 5d.

In the following, each time the material on the rolling line reaches the detection position, the next extracted material is modified. That is, the material extracted after the reaching material (after the reaching material)
The next extraction scheduled time is corrected by the time (corresponding to the substantial delay time) obtained by subtracting the total value of the time of finally correcting the extraction time for the subsequent material) from the prediction error at the detection position of the same material. The maximum value of the correction amounts thus obtained is used at each detection position of each material. This makes it possible to remove the time reflected in the extracted material from the time delayed by the same cause, and automatically take in the delay on the rolling line without lowering the rolling efficiency and reduce the extraction pitch. Can be corrected. As a result, even if the material extracted at the specified extraction pitch is on several rolling lines, and even if the material transfer schedule fluctuates due to a sudden failure of equipment or manual intervention by an operator, loss of rolling opportunities is avoided. , Smooth operation can be realized. Along with this, it becomes possible to reduce the unit fuel consumption of the heating furnace by an amount corresponding to the shortened furnace time.

[0011]

The heating furnace extraction time determination method according to the present invention is configured as described above, so that a plurality of steel materials extracted at a predetermined extraction pitch are present on the rolling line and the equipment suddenly changes. Even if the material transport schedule fluctuates due to a failure or manual intervention by the operator, the next extraction material is corrected by correcting the maximum value of the time difference between the predicted value and the actual value that is known at that time, and In the subsequent furnace material, the scheduled extraction time is corrected by the time excluding the time already reflected from the time difference between the predicted value and the actual value due to the same cause, thereby avoiding loss of rolling opportunity and smoothing. Operation can be realized. Further, with this, the fuel consumption rate of the heating furnace can be reduced by the amount corresponding to the shortening time of the material time.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a schematic flow of a heating furnace extraction time determination method according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing a schematic configuration of a hot rolling line (shared with a conventional example).

FIG. 3 is an explanatory view showing a threading state of a hot rolling line (shared with a conventional example).

FIG. 4 is a diagram showing a schematic flow in an example of a conventional heating extraction time determination method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Heating furnace 2 ... Rough rolling mill 3 ... Finish rolling mill 4 ... Coiler

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Claims (2)

(57) [Claims] 1. Material extracted from a heating furnace to a rolling line
Reaches one or more detection positions provided on the rolling line.
Predicts the time of arrival and measures the actual time.
Newly extracted based on the delay time relative to the predicted value
In the heating furnace extraction time determination method for correcting the scheduled extraction time of a material, the time of the delay for each material arriving at each of the detection positions is determined.
The above extraction scheduled time of each subsequent material already extracted from between
The actual delay time obtained by subtracting the correction time used to correct
Calculated for each material arriving at each of the above detection positions.
A method for determining a heating furnace extraction time, wherein the maximum value of the real delay time obtained above is added to a scheduled extraction time of a newly extracted material. 2. The heating furnace extraction time determination method according to claim 1, wherein the correction time is a time obtained by accumulating past correction times.